Improvement in sewing-machines



A. B. SHAW.

f Sewing Machine.

No. 37,202. Patented Dec.v 16.- 1862.

figg;

UNITED STATES PATENT OFFICE.

A. B. SHAV, OF TORO/ESTER, MASSACHUSETTS, ASSIGNOR TO HIMSELF AND N. H.SHAW, OF SAME PLAGE.

IMPROVEMENT IN SEWING-MACHINES.

Specilcation forming part of Letters Patent No. 37,202, dated December16, 1862.

To all whom z't may concern:

Be itknown that I, A. B. SHAW, of the city of Worcester, in the countyot' Worcester and State of Massschusetts, have invented certain nen1 anduseful Improvements in Sewing-Machines; and l do herebydeclare that thefollowing is a full, clear, and exact description ot' the same,reference being had to the accompanying drawings, forming part of thisspecication, in which- Figure l is a front view of a machine with myimprovements. Fig. 2 is a vertical section at right angles to Fig. 1,exhibiting the mechanism for holding down and feeding the cloth or othermaterial to be sewed. Fig.3 is a top view ot' the looper and itsoperating mechanism. Fig. 4 is a side view corresponding with Fig. 1.Fig. 5 isa View similar to Fig. l, but showing the parts in a differentposition. Fig. 6 is a side view of the looper.

Similar letters of reference indicate correspondingparts in the severalfigures.

To enable others skilled in the art to make and use my invention, I willproceed to describe its construction and operation.

A is the stand or fratrie ot' the machine, and B the work-bed, bolted tothe lower part ot'the stand A.

C is the driving-wheel, arranged to rotate upon a ixed stud, a, at theopposite end of the machine to where the needle is situated, andcarrying a spur-gear, D, which gears with a spur-gear, E', on theneedle-operating and feed-operating shaft E, and with a spur-gear, F',on the looper-operating shaft F,the said shafts being arranged parallelwith each other, the latter in bearings under the work-plate and at theback of the machine and the former in bearings in the upper part of theframing. The shaft E carries a crank or eccentric wrist, b, foroperating the needle-bar G, a cam, C, for operating the feed-lever H,and a cam, d, for taking the pressure ott' the feeding and pressing footpieces. The shaft F carries a crank or eccentric wrist, e, for producingthe operation of the looper I. l

The looper l is attached to or made in the same piece with an arm, i, atthe bottom of which is formed a pivot, f, which is received in a bearingin a stud, g, which is firmly secured in a slotted rocker, J, whichrocks on a xed horizontal pin, h, securedoin the lower part ot' that endof the stand VA next the needle. The said looper has two movementsviz.,a longitudinal one, produced by the move ment of the rocker J, abovementioned, and a lateral one, produced by the vibration of-the arm t'from the pivotf.

The' above-mentioned lateral vibration ot the arm t' is produced by itsbeing carried, in its movement with the rocker, back and forth throughthe curved slot 7c, provided in a stationary plate K, (shown best inFig. 3,).

secured lto the stand A. The vibrating movement ot' the rocker J isproduced h'vthe revolution of the crank or eccentric-wrist pin e, beforementioned, in the slotj, provided in the said rocker for its reception,the slot being so formed and the wrist e so arranged as to propelly timethe movements ot' the looper relatively to those of the needle, as willbe presentl y described.

To prevent any strain ot` the pivotf or stud gbeing produced in theworking of the looper, two steady-vpins, in m, are provided in therocker J for the arm 4i to work between. The looper is curved verticallyin a t'orm approximating to that of an arc concentric with the axis ot'the pin h. It also has a short lateral curvature, as shown atp in Fig.3, the hollow side being toward the needle, and has an eye, n, in frontot` and an eye, o, behind the saidV curvature, and a groove betweenthese eyes on the side farthest from the needle.

rEhe operation of the looper relatively to the needle q in making thestitch is produced as follows: When the needle has descended through thecloth to its lowest position the looper is in the position shown in Fig.5. As the needle rises the looper advances, the arm i working inthestraight part ot' the slot and the looper passing between the needleand its thread and retaining upon itself a loop of the needle-thread.Just as the curve p ot' the looper arrives at the needle the arm i'.arrives at a bend in the slot 7c, and the looper, in its continuedadvance, is caused by the form ot' the said slot to receive a lateralmovement toward the path of the needle, the point of which has now risenabove it, and as the needle descends again through the clothl it iscaused to pass within the curvep of thelooper,

between the latter and the portion ofthe loekl y, is provided in thelower leaf of the spring in g-thread, which is extended straight acrossthe said curve fromthe eye n. As the looper retires it moves laterallyin the opposite direction to that above mentioned, and its point isthereby drawn out ofthe way of the needle. The lateral movement andlateral curvature of the looper combine to insure the passage of theneedle into the loops ofthe looper-thread.v

The feed-lever H, carrying the jointed feeding and pressing foot L, isfitted into a vertical slot, r 1, in the stand A, the part received inthe said slot having rounded protuherances s s on each side to bearagainst the sides ot' the said slot in such a manner as to permit thefree vibration of thelever, as well as a free upward and downwardmovement thereof'. The said lever is made with a yoke, H', for thereception of the cam c, and fitted with a setserew, t, to regulate thefeed, as in manyother sewing-machines. The downward pressure upon `thesaid lever is-produced by a spring, a o, made in two leaves, of whichthe upper leaf, u, is secured firmly to the top ofthe stand, and thelower leaf', o, is attached to the upper one, u, by a rivet, w, or othermeans, in such a manner as to permit it to have an independent upwardand downward movement. The upper leaf, a, does not touch the lever H,but the endvof the lower one, o, enters a transverse notch in the saidlever.

Between the spring and the cam d there is arranged a pin, which isfitted to slide vertically in a guidein the standard A, and a hole,

for the said pin to pass freely through. Thile the needle is in thecloth and the lever is returning with the foot L, preparatory to a newfeed-movement, the cam, by its action through the pin .ron the upperleaf ofthe spring, raises the said leaf, and so removes the pressure ofthe spring from the lever and foot, allowing the latter to slide freelyover the cloth, the

lower leaf ofthe spring then hanging loose below the upper one; butbefore the needle is drawn out of the cloth the cam passes round farenough to let the upper leaf of the spring descend, and the two leavesot' the spring then combine to press upon thelever and foot, andcontinue to do so until the needle has again entered the cloth, when thecam again raises the upper leaf.

I do not claim broadly giving the looper a lateral as well as alongitudinal movement; nor do I claim broadly taking the pressure oli'the foot or pressure pad of a sewing-machine while the needle is-in thecloth; but

What I claim as my invention, and desire to secure by Letters Patent,is-

The combination ot' the lifting-cam and pin .r with the lever Handsprings at, in theman-v uer and for the purpose herein shown anddescribed. t

A. B. SHAW.

Witnesses HERBERT A. SHAW, NA'LHL. M. SHAW.

